Singlet stateIn quantum mechanics, a singlet state usually refers to a system in which all electrons are paired. The term 'singlet' originally meant a linked set of particles whose net angular momentum is zero, that is, whose overall spin quantum number . As a result, there is only one spectral line of a singlet state. In contrast, a doublet state contains one unpaired electron and shows splitting of spectral lines into a doublet; and a triplet state has two unpaired electrons and shows threefold splitting of spectral lines.
SunlightSunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light. On Earth, sunlight is scattered and filtered through Earth's atmosphere, and is obvious as daylight when the Sun is above the horizon. When direct solar radiation is not blocked by clouds, it is experienced as sunshine, a combination of bright light and radiant heat. When blocked by clouds or reflected off other objects, sunlight is diffused.
Nawabs of BengalThe Nawab of Bengal (বাংলার নবাব, ) was the hereditary ruler of Bengal Subah in Mughal India. In the early 18th-century, the Nawab of Bengal was the de facto independent ruler of the three regions of Bengal, Bihar and Orissa which constitute the modern-day sovereign country of Bangladesh and the Indian states of West Bengal, Bihar and Odisha. They are often referred to as the Nawab of Bengal, Bihar and Orissa (বাংলা, বিহার ও উড়িষ্যার নবাব). The Nawabs were based in Murshidabad which was centrally located within Bengal, Bihar, and Odisha.
History of BengalThe history of Bengal is intertwined with the history of the broader Indian subcontinent and the surrounding regions of South Asia and Southeast Asia. It includes modern-day Bangladesh and the Indian states of West Bengal, Tripura and Assam's Karimganj district, located in the eastern part of the Indian subcontinent, at the apex of the Bay of Bengal and dominated by the fertile Ganges delta. The region was known to the ancient Greeks and Romans as Gangaridai, a powerful kingdom whose war elephant forces led the withdrawal of Alexander the Great from India.
West BengalWest Bengal (bɛnˈɡɔːl, Bengali: Poshchim Bongo, ˈpoʃtʃim ˈbɔŋɡo, abbr. WB) is a state in the eastern portion of India. It is situated along the Bay of Bengal, along with a population of over 91 million inhabitants within an area of as of 2011. The population estimate as of 2023 is 102,552,787. West Bengal is the fourth-most populous and thirteenth-largest state by area in India, as well as the eighth-most populous country subdivision of the world.
Rose bengalRose bengal (4,5,6,7-tetrachloro-2',4',5',7'-tetraiodofluorescein) is a stain. Rose bengal belongs to the class of organic compounds called xanthenes. Its sodium salt is commonly used in eye drops to stain damaged conjunctival and corneal cells and thereby identify damage to the eye. The stain is also used in the preparation of Foraminifera for microscopic analysis, allowing the distinction between forms that were alive or dead at the time of collection. A form of rose bengal is also being studied as a treatment for certain cancers and skin conditions.
DiradicalIn chemistry, a diradical is a molecular species with two electrons occupying molecular orbitals (MOs) which are degenerate. The term "diradical" is mainly used to describe organic compounds, where most diradicals are extremely reactive and in fact rarely isolated. Diradicals are even-electron molecules but have one fewer bond than the number permitted by the octet rule. Examples of diradical species can also be found in coordination chemistry, for example among bis(1,2-dithiolene) metal complexes.
Body waterIn physiology, body water is the water content of an animal body that is contained in the tissues, the blood, the bones and elsewhere. The percentages of body water contained in various fluid compartments add up to total body water (TBW). This water makes up a significant fraction of the human body, both by weight and by volume. Ensuring the right amount of body water is part of fluid balance, an aspect of homeostasis. By weight, the average adult human is approximately 70% water, and the average child is approximately 60% water.
Radical anionIn organic chemistry, a radical anion is a free radical species that carries a negative charge. Radical anions are encountered in organic chemistry as reduced derivatives of polycyclic aromatic compounds, e.g. sodium naphthenide. An example of a non-carbon radical anion is the superoxide anion, formed by transfer of one electron to an oxygen molecule. Radical anions are typically indicated by . Many aromatic compounds can undergo one-electron reduction by alkali metals.
Bengal famine of 1943The Bengal famine of 1943 was an anthropogenic famine in the Bengal province of British India (present-day Bangladesh, West Bengal, Odisha and eastern India) during World War II. An estimated 2.1–3 million people died, in the Bengal region (present-day Bangladesh and West Bengal), from starvation, malaria and other diseases aggravated by malnutrition, population displacement, unsanitary conditions and lack of health care. Millions were impoverished as the crisis overwhelmed large segments of the economy and catastrophically disrupted the social fabric.